25/4/09
AB Big Idea:Negative numbers help us to model many real world situations.
Essential Question #4: How do I multiply and divide integers? Notes: None
Qa1) Suppose the temperature changed by an average of +3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total temperature change for the five hours.
Ans:
Number of hours
1
2
3
4
5
Total Temperature Change
3 degrees
6 degrees
9 degrees
12 degrees
15 degrees
Q2) Write a multiplication sentence that represents the total change in temperature for the first five hours. Write a multiplication that represents the total change in the temperature for the entire 10 hour period.
Ans)15 degrees because 3 degrees times 5 is 15 degrees. For the intire 10 period is 30 degrees because 10 times 3 is 30. QB1) Suppose the temperature changed by an average of -3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total tempreture change for the first 5 hours.
Ans)
Number of hours
1
2
3
4
5
Total temperature change
-3
-6
-9
-12
-15
QB2) Write a multiplication sentence that represents the total change in temperature for the entire 10 hour period.
Ans) The first 5 hours is -15 because (-3 x 5= 15) The first 10 hour period is -30 because (-3 x10=-30) QC1)Write the addition sentence illustrated by each diagram below. 2)Write the multiplication sentence illustrated by each diagram below
Ans)1. Addition sentences are :
a)+2+(+2)+(+2)= +6
b)-3+(-3)= -6
c)-2+(-2)+(-2)+(-2)= -8
2)Multiplication sentences are :
a) 2x3=6
b)-3x2= -6
c) -2x4= -8 QD) Make up a situation about temperatures that can be expressed as 4x -10
Ans)
of hours
1
2
3
4
Total temperature change
-10
-20
-30
-40
QE) Find each product.
1. -20
2.-80
3.-80
4.-20
Follow up 1. Suppose the tempreture changed by an answer of +2 degrees per hour from its low of -4 F at 3:00 A.M. What was the tempreture at 1:00 P.M.?
Ans)1) At 1:00 P.M the tempreture was 16 F 2. Suppose the tempreture changed by an average of -1.5 degrees from its high of +25 F at noon. What was the tempreture at 10:00 P.M.?
2)At 10:00 A.M. the temnpreture was 40 F 3. When you add a positive integer and a negitive integer, you sometimes get a positive result and sometimes get a negetive results. Is the same true when you multiply a positive integer and a negetive integer? Explain.
Ans) No because every time we multiply a positive and a negetive number we always get a negetive value. Example: -5x3 = -15
AB
Big Idea:Negative numbers help us to model many real world situations.
Essential Question #4: How do I multiply and divide integers?
Notes: None
Qa1) Suppose the temperature changed by an average of +3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total temperature change for the five hours.
Ans:
Ans)15 degrees because 3 degrees times 5 is 15 degrees. For the intire 10 period is 30 degrees because 10 times 3 is 30.
QB1) Suppose the temperature changed by an average of -3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total tempreture change for the first 5 hours.
Ans)
Ans) The first 5 hours is -15 because (-3 x 5= 15) The first 10 hour period is -30 because (-3 x10=-30)
QC1)Write the addition sentence illustrated by each diagram below.
2) Write the multiplication sentence illustrated by each diagram below
Ans)1. Addition sentences are :
a)+2+(+2)+(+2)= +6
b)-3+(-3)= -6
c)-2+(-2)+(-2)+(-2)= -8
2)Multiplication sentences are :
a) 2x3=6
b)-3x2= -6
c) -2x4= -8
QD) Make up a situation about temperatures that can be expressed as 4x -10
Ans)
1. -20
2.-80
3.-80
4.-20
Follow up
1. Suppose the tempreture changed by an answer of +2 degrees per hour from its low of -4 F at 3:00 A.M. What was the tempreture at 1:00 P.M.?
Ans)1) At 1:00 P.M the tempreture was 16 F
2. Suppose the tempreture changed by an average of -1.5 degrees from its high of +25 F at noon. What was the tempreture at 10:00 P.M.?
2)At 10:00 A.M. the temnpreture was 40 F
3. When you add a positive integer and a negitive integer, you sometimes get a positive result and sometimes get a negetive results. Is the same true when you multiply a positive integer and a negetive integer? Explain.
Ans) No because every time we multiply a positive and a negetive number we always get a negetive value. Example: -5x3 = -15